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Discussion on: Day 8 : Learning JS fundamentals, Part -3

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marzelin profile image
Marc Ziel •

It is all about the call, it is not the definition of the function, it is not where the function is, none of that matters, it is only how the function was called that determines where the this keyword will be pointing to.

This isn't entirely true. You can bind a function and that sets this at creation time. Only new operator can change what this refers to on a binded function at call time.

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gauravshekhawat profile image
Gaurav-Shekhawat •

Can you please elaborate, I am not able to understand. A link or something regarding the same will suffice.

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marzelin profile image
Marc Ziel •

If you bind a function:

const bound = function () {
   console.log(this);
}.bind({type: "bound"});
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then no matter how you call the function (except new).
You can use .:

const o = { bound, type: "dot notation" };
o.bound();
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apply or call:

bound.call({type: "call"});
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or even call it directly:

bound();
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but this will always be the bound object: {type: "bound"}.

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gauravshekhawat profile image
Gaurav-Shekhawat •

thank you so much for your assistance